IT'S being called Silk Trail 2013 because the cars will be taking the route used by silk traders in the days before DHL and air freight.

Leaving from Solihull, the caravan will make its way through France, Poland, Russia and China, crossing a few countries that are too difficult to spell en route. Like Uzbekiwhatsit.

Then, in the middle of October, the three-car convoy will arrive at Land Rover owner Tata’s headquarters in Mumbai, India.

Apart from the near two-month trip being a jolly good blag for the journalists who will be joining the Silk Trail, the expedition intends to show off Land Rover’s new hybrid Range Rover and Range Rover Sport models.

Both use the same combination of a 3.0-litre V6 diesel engine and 35kW electric motor, and both drive through an eight-speed automatic gearbox in any of three driving modes.

In pure electric mode, the Range Rovers can reach 30mph and cover a mile before the diesel engine restarts and helps out. The combined power output of both the diesel and electric motors is 335bhp, which gives the Sport a 0-60mph time of 6.7 seconds and a top speed of 140mph (the Range Rover does 0-60mph in 6.9 seconds and has a top speed of 135mph).

The Hybrid can zip to 60mph in less than seven seconds (Photo: Range Rover)

But what this hybrid lark is all about is fuel economy. Land Rover say that, on the combined cycle, both models will return 44.1mpg.

That’s a test figure, but even 35mpg would be impressive in big SUVs.

Also, the hybrid is more economical than the V8 diesel, yet has comparable performance.

But what Land Rover are most keen to demonstrate, and this is why they are driving three cars all the way to Mumbai when you can pick up a good curry locally, is that both the Range Rover and the Sport are still supreme off-roaders.

The cars’ liquid-cooled battery pack is mounted beneath the floor in a tough boron steel cradle, which keeps the weight low and also doesn’t rob the cars of ground clearance or wading ability.

In fact, everything conventional Range Rovers can do off-road can be matched by these new hybrids.

The order books for the new hybrid models open after the Frankfurt Motor Show next month, when prices will also be announced.